C# - Datatable to CSV using LINQ

Category > LINQ || Published on : Monday, September 21, 2020 || Views: 2704 || C# - Datatable to CSV using LINQ


This article we are going to learn to convert Datatable to CSV in c# and explains the efficient way to write CSV files from Datatable

aspx source code

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="datatable-CSV-linq.aspx.cs" Inherits="datatable_CSV_linq" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <asp:Button ID="btnConvert" runat="server" Text="datatable to CSV" OnClick="btnConvert_Click" />
        </div>
    </form>
</body>
</html>

code behind source code

using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;

public partial class datatable_CSV_linq : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    public DataTable GetData()
    {
        DataTable dt = new DataTable();
        try
        {
            dt.Columns.Add("CustomerId", typeof(int));
            dt.Columns.Add("CustomerName", typeof(string));
            dt.Columns.Add("ProductName", typeof(string));
            dt.Columns.Add("Price", typeof(double));
            dt.Rows.Add(1, "Shahrukh", "desktop", 65000);
            dt.Rows.Add(2, "Salman", "keyboard", 1120);
            dt.Rows.Add(3, "Amir", "RAM", 8900);
            dt.Rows.Add(4, "Akshay", "Ryzen 5 3600", 20000);
            dt.Rows.Add(5, "Dev", "Mouse", 596);
            dt.Rows.Add(6, "Kishor", "RGB Fan", 400);
            return dt;
        }
        catch (Exception ex)
        {
            return null;
        }
        finally
        {
            if (dt != null)
            {
                dt.Dispose();
                dt = null;
            }
        }
    }

    protected void btnConvert_Click(object sender, EventArgs e)
    {
        try
        {
            DataTable dtCSV = new DataTable();

            dtCSV = GetData();

            if (dtCSV != null && dtCSV.Rows.Count > 0)
            {
                StringBuilder sb = new StringBuilder();

                string[] columnNames = dtCSV.Columns.Cast<DataColumn>().Select(column => column.ColumnName).ToArray();

                sb.AppendLine(string.Join(",", columnNames));

                foreach (DataRow row in dtCSV.Rows)
                {
                    IEnumerable<string> fields = row.ItemArray.Select(field => string.Concat("\"", field.ToString().Replace("\"", "\"\""), "\""));
                    sb.AppendLine(string.Join(",", fields));
                }
                File.WriteAllText(Server.MapPath("/data.csv"), sb.ToString());
            }
        }
        catch (Exception ex)
        {
            throw;
        }
    }
}